Internal combustion engine



' Feb. 12, 1935. Mensa; 1,991,213

INTERNAL COMBUSTION ENGINE Filed Aug. 20, 1930 I s Sheets-Sheet 1 fir! @car ameli L 9 a 1 N 212%5 201-57 Feb. 12, 1935. R c sc INTERNAL COMBUSTION ENGINE Filed Aug. 20, 1930 .3 Sheets-Sheet 2 w ww Feb. 12, 1935. R. JACKISCH INTERNAL COMBUSTiON ENGINE 5 Sheets-Sheet 3 Filed A115. 20, 1930 N% QR MN 1 MN NM NW k 1 F 1 1| 1 1 1..., I! k 1/1 II HI m kw QM mm \Q Q \Q \R Mm Patented Feb. 12, 1935 UNITED STATES PATENT, OFFICE 1,991,218 INTERNAL COMBUSTION ENGINE Rudolph Jackisch, Chicago, Ill. Application August 20, 1930, Serial No. 476,509

4 Claims. (Cl. 123-3?) This invention relates to internal combustion engines, and more particularly engines of the type which operate on the high compression principle wherein the fuel is injected into the combustion chamber containing a body of air which is under high compression and at a temperature above the igniting temperature of the fuel.

The principal object of the invention is to improve generally upon engines of the character above noted by simplifying and making more compact the structure thereof, and by providing for the creation of uniform compression within thev combustion chamber under all conditions but at the same time varying the quantity of air and feeding a proportionately measured supply of the fuel into the combustion chamber in accordance with the work load imposed upon the engine. Other objects and advantages to, be attained will hereinafter more fully appear.

The invention consists in the general structure and in the several parts and combinations and arrangements of parts thereof as hereinafter specified and pointed out with particularity in the appended claims.

In the accompanying drawings, illustrating a practical adaptation of the invention,--

Fig. 1 is a partial side elevation and longiopposed pistons in the power cylinder being in their respective innermost positions;

Fig. 3 is a similar section, the pistons being in their relative outermost positions;

Fig. 4 is a view, similar to Fig. 3, wherein the pistons have moved some distance on their instrokes; and

Fig. 5 is a detail view, on an enlarged scale, illustrating the means for longitudinally adjusting the cam shaft.

Referring now to the adaptation of the invention as illustrated in the drawings, the numeral designates the main body portion of the engine which, as shown, comprises a unitary casting in which two parallel power cylinders 17 areformed, each cylinder 17 having a pair of opposed reciprocatory pistons 20, 21, working therein.

The pistons 20 and 21 are provided with pitman rods which are guided in cylindrical extensions 47 of a cover plate or head 48 which is provided to close the ends of the cylinders 1'7, said ings is' for the two-cycle type of operation, and will be now so described. The connections between the respective'pistons and the crankshaft are such that when the cooperating pair of opposed pistons 20, 21, in the one cylinder 17 are at their innermost meeting positions and the particular crank portion 49 of the crankshaft 50 to which the pistons are correlated is at its inner dead central position, the pair of pistons 20 and 21 in the other cylinder 17 are in their outermost remote positions and their correlated crank portion 49 of the crankshaft 50 is at its outer dead central position. By the manner of connecting the pistons with the crankshaft the power of the pistons in the one cylinder in moving on their outstrokes under the force of the ignited combustible charge draws the pistons in the other cylinder simultaneously inward.

As the pistons in each of the cylinders 17 reach the limit of their outstrokes they respectively un-' cover a port 52 which is in communication with an inlet 53 from a source of compressed air supply (not shown) and a port 54 which communicates with an exhaust outlet 55. During the time the ports 52 and 54 are open the air under pressure entering the cylinder through the port 52 drives the foul products of combustion out through the exhaust port 54, and as the' two pistons move on their instrokes and cover said ports, as shown in Fig. 4, the air in the cylinder is compressed between the pistons and into an auxiliary chamber 56 communicating with the cylinder through a slotted opening 57, said chamber 56 combined with the limited space between the meeting ends of the pistons when at their innermost positions (see Fig. 2), constituting the combustion chamber, as will now be set forth.

Communicating with the combustion chamber as above described, in the region of the slot 5'7, is a nozzle 58 which has a restricted passageway 59 communicable with a small bore 60 in which works a plunger 61, said bore having communication with a fuel receiving chamber 62 through an inwardly opening check valve 63, and also through an outwardly opening check valve 64, said chamber 62 being connected through a pipe 65 to a source of fuel oil supply underpressure (not shown).

The plunger 61 is moved in one direction and normally held in engagement with an actuating cam 66 by a spring 67, said spring, as shown, being coiled about the plunger and located in a housing 68, one end of the spring bearing against a shoulder 69 on the housing and its opposite end bearing against a shoulder '70 afforded by an enlargement 71 of said plunger, said enlargement being provided at its outer end with a roller 72 for engaging the cam 66.

The cam 66 which, as shown, is a cylindrical body having a circumferential recess of varying depth and width, always acts to move the plunger 61 to the same forward position, but by the provision of the said circumferential recess therein, designated by the numeral 73 upon shifting the cam longitudinally of its axis, the plunger 61 is variably retracted by the spring 67. That is to say, while the normal cylindrical surface of the cam 66 is in engagement with the roller 72 the inner end portion of the plunger 61 is at a definite position in the bore 60, and said plunger remains in this position until the recessed portion 73 moves into engagement with the roller 72, whereupon the spring 67 reacts to move the plunger back to a position which is determined by the position of the cam 66 to which it is longitudinally adjusted. The adjustment of the cams 66, of which there are two, being one for each of the power cylinders 17 and set at diametrically opposite relation to each other on a shaft 74, is effected by shifting the shaft 74 longitudinally in its bearings.

For shifting the shaft 74 it may be journaled conveniently at one end in a tubular member or sleeve 75, said sleeve 75 being slidable through an opening in a. boss 76 on one of the side walls 77 of the crankcase, said sleeve being prevented from rotation by having a longitudinal slot 78 in' which a feather key or spline 79 on the boss 76 slidably engages. An anti-friction bearing 80 is provided at the inner end portion of said sleeve 75 for the shaft 74, while within the sleeve is an annular groove 81 which constitutes a raceway for a ball bearing 82, said bearing 82 serving the dual function of journal bearing and an end thrust bearing whereby the shaft 74 is free to rotate in the sleeve 75 but is moved simultaneously lengthwise therewith. The sleeve 75 is externally screw-threaded, as at 83, and has a nut 84 thereon which, as shown, is the hub portion of a hand wheel 85, said nut or hub portion having an annular circumferential groove 86 slidably engaged by lugs 87 provided at the ends of angle brackets 88 which are secured to the wall 77 of the crankcase by the bolts 89. By turning the hand wheel 85, which is held in place by the engagement of said anglebrackets 88, the feather-keyed tubular member or sleeve 75 is moved endwise and moves the shaft 74 with it.

On the camshaft 74 is aflixed a spur gear 90 which slidably engages a relatively wide faced gear 91, which is fixed on a countershaft 92, this slidingengagement of the gear 90 with the gear 91 permitting the longitudinal movement of the shaft 74 while said gears remain in mesh with each other. On the shaft 92 is a bevel gear 93 which meshes with a corresponding gear 94 on the end of a right angular driving shaft 95, which latter is provided at its opposite end with a bevel gear 96 meshing with a similar gear 97 on a stub shaft 98, having a second gear 99 thereon. The gear 99 is in mesh with a gear 100 on the end of the crankshaft 50. By the gearing just above described the camshaft 74 rotates simultaneously and at the same speed with the crankshaft 50. That is to say, for each revolution of the crankshaft the camshaft makes one complete revolution therewith.

In the operation of the engine the port 52, which is covered and closed by one of the pistons in the power cylinder except during the time the piston is at the limit of its outstroke and while nearing such limit, and during the initial part of the movement on its instroke, is connected through the inlet 53 with a source of compressed air supply. The exhaust port 54 is closed to atmospheric communication through the outlet 55 except during the time the opposed piston is at or near the limit of its outstroke, and during the initial movement on its instroke. At all times the fuel supply pipe 65 is in communication with a source of supply under pressure and the receiving chamber 62 is maintained full of fuel under pressure from the supply pipe 65, said fuel being supplied to the small bore or measuring chamber 60 through the check valve 63. Assuming that the opposed pair of pistons in the power cylinder are at the end of their outstroke, as illustrated in Fig. 3 of the drawings, the ports 52 and, 54 are uncovered and compressed air is entering through the port 52 into the cylinder between the two pistons and passing out through the exhaust port 54, thereby clearing the cylinder of the foul products of combustion. As the two pistons move on their instrokes under power due to the momentum of the flywheel on the crankshaft, and the pistons in the companion cylinder which are moving on their outstrokes under the force resulting from the combustion of the fuel in the compressed body of air between them, the air confined in the cylinder between the two inwardly moving pistons is compressed to a high degree and becomes heated to an exceedingly high temperature within the confines of the chamber 56 and the restricted space between the meeting ends of the two pistons as the latter reach the limit of their instrokes. At this time the recessed portion 73 of the cam 66 is in a position to receive the roller 72 at the outer end of the plunger 61, and the plunger is retracted by the spring 67, thereby moving its inner end por tion clear of the entrance to the passageway 59 in the nozzle 58.

During the receding movement of the plunger 61 the fuel under pressure in the receiving chamber 62 passes through the check valve 63 and fills the space in the small bore or measuring chamber 60 vacated by the receding piston, it, of course, being understood that the pressure of the fuel oil is equalized with the pressure in the combustion chamber. As the correlated crank 49 on the crankshaft 50 swings from its inner dead central position and the pistons begin to move on their outstrokes the recessed portion 73 of the cam 66 moves out of engagement with the roller 72 on the plunger 61, thereby forcing the plunger inwardly and the latter in turn displacing the fuel in the bore 60 and forcing a portion of the fuel through the passageway 59 in the nozzle 58.

As soon as the fuel from the nozzle 58 is injected into the body of air which is compressed in the combustion chamber and thereby heated to a temperature higher than the combustion point of the fuel oil, combustion occurs and continues as long as the plunger 61 is moving inward and forcing the fuel oil through the nozzle 58. When the recessed portion 73 of the cam 66 is moved clear of the roller 72 and the cylindrical circumferential portion of the cam is in engagement with the roller, the plunger 61 has moved a distance suflicient to cover the entrance to the passageway 59 of the nozzle 58 and remains in this relation until the pistons have completed their outstrokes.

While the engine is running under a heavy load the compressed combustible mixture a maximum charge of the fuel oil; However, if it is unnecessary to supply the full maximum charge of fuel oil, camshaft 74 is shifted longitudinally in opposite direction, by turning the hand wheel 85 reversely, thereby bringing the cam 66 into position where the shallower portion of the recess 73 engages the roller 72 on the plunger 61, which restricts the receding movement of the plunger, but it is to be understood that in any case the plunger moves on its receding stroke. a distance sufliciently to uncover the end of the passageway 59 in the nozzle 58 that communicates with the small bore or measuring chamber 60.

In some cases, where the engine is running under a light load and requiring only a minimum power, further provision is made for reducing the volume of the fuel oil and the free air within the combustion chamber. This is accomplished by providing a transverse opening 101 in the plunger 61 which is adapted to establish communication between an exhaust passageway 102 in the cylinder and a port 103. Normally, the transverse opening 101 in the plunger 61 does not move into cooperative relation with the exhaust passageway 102 and port 103- during the regular operation of the engine as just above described,

5 but said opening 101 is brought into communicable registration with said passageway and port, as will now be described, by the engagement of a peripheral extension 104 on the cam 66 when the cam is shifted to bring the shallower portions of its circumferential recess 73 into the path of the roller 72 on the plunger 61. This peripheral projection 104 on the cam is positioned so as to operate the plunger 61 and bring its transverse opening 101 into registration with the exhaust passageway 102 and port 103 just after the pistons in the power cylinder have moved on their instrokes sufficiently to cover. the scavenging ports 52 and 54. a

The forward end portion of the peripheral face of said projection 104 is straight and substantially parallel with the axis of the shaft 74, while its rear end portion is inclined, so that when the projection is operating, the opening 101, passageway 102 and port 103 are always made to register at the same instance, in whatever position the projection may be, but remain in communication during varying intervals, or until said projection 104 rides out of engagement with the roller 72, which latter then engages the circumferential face of the cylindrical portion of the cam 66, and thereby permits the plunger to recede sufllciently to bring the opening 101 out of registry with said passageway 102 and port 103. Obviously, on the continued instrokes of the pistons after the passageway 102 has been opened and again closed, as just hereinbefore described, the remaining air in the cylinder is compressed to the same degree as when the engine is operating under ordinary conditions. When the pistons reach their innermost positions the cam recess '73 is brought into receiving relation with respect to the roller 72, and the plunger 61 is retracted by the spring 67 to uncover the passageway 59 of the fuel nozzle 58. The position of the plunger 61 being thus limited by the engagement of the roller 72 with the relatively shallow part of the cam recess '73, only a relatively small quantity of fuel oil will be ejected from nozzle 58 as the cam recess moves out of engagement with the roller and the circumferential face of the cylindrical portion of the cam rides into engagement with the roller at the time the pistons are starting on their outstrokes.

In order to provide for relief of undue pressure in the small bore or measuring chamber 60, which might interfere with the plunger 61 on its forward or charge ejecting movement, the outwardly opening check valve 64 is provided, which controls communication between said bore 60 and the receiving chamber 62 through openings 106 and 107, said check valve being yieldably held to its seat by a spring 108 which is set to resist a given pressure, or the tension of which may obviously be adjusted by manipulating the retaining screw 109. I

From the foregoing it is apparent that a substantially uniform compression is attained under all conditions, but the quantity of free air-and fuel oil for the combustible mixture is varied, at will, to suit different load conditions imposed upon the engine; and it is to be understood that the present invention is applicable to engines operating incycles different from that in the particular engine herein illustrated, and described, and that, while the engine may be arranged with its cylinders disposed side by side and in a horizontal plane with the crankshaft rotating about a vertical axis as illustrated in the drawings, obviously the cylinders may be disposed horizontally with one above the other and the crankshaftrotating about a horizontal axis, or the cylinders may be vertically disposed, and manyother modificaitons in the details and arrangements of the several parts may be made and substituted for those herein shown and described withoutin the least departing from the spirit-and scope of the invention as defined by the appended claims. The invention, therefore, is not limited to the specific construction and arrangement shown in the accompanying drawings.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

1. An internal combustion engine of the high compression ignition type, having a restricted auxiliary compression chamber in communication with the combustion chamber proper, means for supplying a compressed air charge to the combustion chamber, means for varying the cubical working capacity of said auxiliary compression chamber, a cooperating fuel supply chamber having a restricted passageway communicating directly with the combustion chamber in the region where the combustion chamber communicates with said auxiliary compression chamber,

means for proportionately varying the quantity of free air in the combustion chamber prior to compressing the air charge, whereby to establish uniform compression in the combustion chamber,

and means for correspondingly supplying a procluding the aforesaid plunger adapted to norports.

3. In an engine of the high compression ignition type, the combination including a casting having a combustion chamber and ports for the exhaust of fuel mixture, means including a plunger for supplying a measured charge of fuel to the combustion chamber, means for supplying compressed air under pressure to the combustion chamber, and means for reducing compression within the combustion chamber, said means including the aforesaid plunger adapted to normally close the aforesaid fuel mixture exhaust ports, said plunger being provided with a port adapted to register with said fuel mixture exhaust ports. I

4. In an engine of the high compression ignition type, a casting having a combustion chamber, an auxiliary combustion chamber connected to said combustion chamber, a measuring chamber, a passageway connecting the measuring chamber with the combustion chamber, a receiving chamber connected to the measuring chamber, and ports for the inlet and exhaust of air and fuel mixture, means for supplying a measured charge of fuel to the combustion chamber, said means including a plunger adapted to reciprocate in said measuring chamber and cause measured amount of fuel to be drawn into the measuring chamber from the receiving chamber and to cause measured amounts of said fuel to be transmitted to said combustion chamber, means for variably actuating said plunger in one direction, said means including a longitudinally adjustable rotatable cam, and for retracting the plunger in the other direction, said means in-- cluding a spring, said cam having a circumferential portion for moving the plunger normally a constant distance in a direction to eject the contents of said measuring chamber through said passageway and having another variable circumferential portion for variably limiting the reverse movement of the plunger, means for adjusting said cam relative to said plunger to vary the retracted portion of the plunger, means for supplying compressed air under pressure, means for reducing compression within the combustion chamber, said means including the aforesaid plunger adapted to normally close the aforesaid fuel mixture exhaust ports, said plunger being provided with a port adapted to register with said fuel mixture exhaust ports, and means for selectively actuating said plunger to open and close the fuel mixture exhaust ports.

' RUDOLPH JACKISCH. 

